The physical downlink control channel (PDCCH) is an important physical channel in the standards of third generation partnership project (3GPP) long term evolution (LTE) and long term evolution-advanced (LTE-A). Downlink control signalling is borne by the PDCCH and is located on the first N orthogonal frequency division multiplexing symbols of each downlink subframe, wherein N is less than or equal to 4.
The downlink control signalling includes the following two parts of contents: 1. a downlink transport format (DTF), a downlink shared channel (DL-SCH), a physical resource allocation result of two transmission channels of a paging channel and DL-SCH related hybrid auto retransmission quest (HARQ) information; and 2. an uplink transport format (UTF), a physical resource allocation result of an uplink shared channel (UL-SCH) and UL-SCH related HARQ information.
In a current downlink subframe, each scheduled UE may detect one or more PDCCHs at the same time. Different PDCCH coding efficiencies are determined by different control channel element (CCE) polymerization degrees and downlink control information (DCI) formats. Each control channel corresponds to a certain x radio network temporary identifier (x-RNTI), and the x-RNTI is configured to user equipment (UE) by high-layer signalling in advance.
A load capacity and power allocation method of the PDCCH have no necessary connection with the load capacity and power allocation method of the physical downlink shared channel (PDSCH) on the same subframe, and depend on a radio resource management algorithm of a device. Generally, 100% resource utilization rate may be achieved for the PDSCH through a proper media access control (MAC) algorithm, therefore, the interference level of an adjacent cell introduced to OFDM symbols where the PDSCH is located is relatively stable. However, a control channel is usually not operated in a full load state, and a PDCCH mapping pattern may change suddenly with the change of the subframe, there are different PDCCH power allocation algorithms, thus easily rendering relatively severe interference fluctuation of an adjacent cell into a control channel region. Therefore, even though it is considered that the PDCCH and the PDSCH experience the same channel fading (or correlation time of a channel is longer than the time length of one subframe), the channel quality prediction to the PDCCH needs to differ from the channel quality prediction to the PDSCH.
However, in the related art, with respect to the channel quality prediction of the PDCCH, an accurate and highly efficient control channel quality prediction method is not given in relevant protocols, and thus a rapid and accurate positioning basis cannot be provided for control channel element resource and power allocation algorithms of an Evolved Node B (eNodeB).